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2017-01-19Merge tag 'for-linus-4.10-rc4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fix from Juergen Gross: "A fix for Xen running in nested virtualization environment" * tag 'for-linus-4.10-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: partially revert "xen: Remove event channel notification through Xen PCI platform device"
2017-01-13partially revert "xen: Remove event channel notification through Xen PCI ↵Stefano Stabellini
platform device" Commit 72a9b186292d ("xen: Remove event channel notification through Xen PCI platform device") broke Linux when booting as Dom0 on Xen in a nested Xen environment (Xen installed inside a Xen VM). In this scenario, Linux is a PV guest, but at the same time it uses the platform-pci driver to receive notifications from L0 Xen. vector callbacks are not available because L1 Xen doesn't allow them. Partially revert the offending commit, by restoring IRQ based notifications for PV guests only. I restored only the code which is strictly needed and replaced the xen_have_vector_callback checks within it with xen_pv_domain() checks. Signed-off-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2017-01-06Merge branch 'stable/for-linus-4.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb Pull swiotlb fixes from Konrad Rzeszutek Wilk: "This has one fix to make i915 work when using Xen SWIOTLB, and a feature from Geert to aid in debugging of devices that can't do DMA outside the 32-bit address space. The feature from Geert is on top of v4.10 merge window commit (specifically you pulling my previous branch), as his changes were dependent on the Documentation/ movement patches. I figured it would just easier than me trying than to cherry-pick the Documentation patches to satisfy git. The patches have been soaking since 12/20, albeit I updated the last patch due to linux-next catching an compiler error and adding an Tested-and-Reported-by tag" * 'stable/for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: swiotlb: Export swiotlb_max_segment to users swiotlb: Add swiotlb=noforce debug option swiotlb: Convert swiotlb_force from int to enum x86, swiotlb: Simplify pci_swiotlb_detect_override()
2017-01-06swiotlb: Export swiotlb_max_segment to usersKonrad Rzeszutek Wilk
So they can figure out what is the optimal number of pages that can be contingously stitched together without fear of bounce buffer. We also expose an mechanism for sub-users of SWIOTLB API, such as Xen-SWIOTLB to set the max segment value. And lastly if swiotlb=force is set (which mandates we bounce buffer everything) we set max_segment so at least we can bounce buffer one 4K page instead of a giant 512KB one for which we may not have space. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reported-and-Tested-by: Juergen Gross <jgross@suse.com>
2017-01-05Merge tag 'for-linus-4.10-rc2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes and cleanups from Juergen Gross: - small fixes for xenbus driver - one fix for xen dom0 boot on huge system - small cleanups * tag 'for-linus-4.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: Xen: ARM: Zero reserved fields of xatp before making hypervisor call xen: events: Replace BUG() with BUG_ON() xen: remove stale xs_input_avail() from header xen: return xenstore command failures via response instead of rc xen: xenbus driver must not accept invalid transaction ids xen/evtchn: use rb_entry() xen/setup: Don't relocate p2m over existing one
2017-01-03Xen: ARM: Zero reserved fields of xatp before making hypervisor callJiandi An
Ensure all reserved fields of xatp are zero before making hypervisor call to XEN in xen_map_device_mmio(). xenmem_add_to_physmap_one() in XEN fails the mapping request if extra.res reserved field in xatp is not zero for XENMAPSPACE_dev_mmio request. Signed-off-by: Jiandi An <anjiandi@codeaurora.org> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2017-01-03xen: events: Replace BUG() with BUG_ON()Shyam Saini
Replace BUG() with BUG_ON() using coccinelle Signed-off-by: Shyam Saini <mayhs11saini@gmail.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-12-25cpu/hotplug: Cleanup state namesThomas Gleixner
When the state names got added a script was used to add the extra argument to the calls. The script basically converted the state constant to a string, but the cleanup to convert these strings into meaningful ones did not happen. Replace all the useless strings with 'subsys/xxx/yyy:state' strings which are used in all the other places already. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-23xen: remove stale xs_input_avail() from headerJuergen Gross
In drivers/xen/xenbus/xenbus_comms.h there is a stale declaration of xs_input_avail(). Remove it. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-12-23xen: return xenstore command failures via response instead of rcJuergen Gross
When the xenbus driver does some special handling for a Xenstore command any error condition related to the command should be returned via an error response instead of letting the related write operation fail. Otherwise the user land handler might take wrong decisions assuming the connection to Xenstore is broken. While at it try to return the same error values xenstored would return for those cases. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-12-23xen: xenbus driver must not accept invalid transaction idsJuergen Gross
When accessing Xenstore in a transaction the user is specifying a transaction id which he normally obtained from Xenstore when starting the transaction. Xenstore is validating a transaction id against all known transaction ids of the connection the request came in. As all requests of a domain not being the one where Xenstore lives share one connection, validation of transaction ids of different users of Xenstore in that domain should be done by the kernel of that domain being the multiplexer between the Xenstore users in that domain and Xenstore. In order to prohibit one Xenstore user "hijacking" a transaction from another user the xenbus driver has to verify a given transaction id against all known transaction ids of the user before forwarding it to Xenstore. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-12-22xen/evtchn: use rb_entry()Geliang Tang
To make the code clearer, use rb_entry() instead of container_of() to deal with rbtree. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-12-19swiotlb: Convert swiotlb_force from int to enumGeert Uytterhoeven
Convert the flag swiotlb_force from an int to an enum, to prepare for the advent of more possible values. Suggested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2016-12-14mm: use vmf->address instead of of vmf->virtual_addressJan Kara
Every single user of vmf->virtual_address typed that entry to unsigned long before doing anything with it so the type of virtual_address does not really provide us any additional safety. Just use masked vmf->address which already has the appropriate type. Link: http://lkml.kernel.org/r/1479460644-25076-3-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-13Merge tag 'for-linus-4.10-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: "Xen features and fixes for 4.10 These are some fixes, a move of some arm related headers to share them between arm and arm64 and a series introducing a helper to make code more readable. The most notable change is David stepping down as maintainer of the Xen hypervisor interface. This results in me sending you the pull requests for Xen related code from now on" * tag 'for-linus-4.10-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (29 commits) xen/balloon: Only mark a page as managed when it is released xenbus: fix deadlock on writes to /proc/xen/xenbus xen/scsifront: don't request a slot on the ring until request is ready xen/x86: Increase xen_e820_map to E820_X_MAX possible entries x86: Make E820_X_MAX unconditionally larger than E820MAX xen/pci: Bubble up error and fix description. xen: xenbus: set error code on failure xen: set error code on failures arm/xen: Use alloc_percpu rather than __alloc_percpu arm/arm64: xen: Move shared architecture headers to include/xen/arm xen/events: use xen_vcpu_id mapping for EVTCHNOP_status xen/gntdev: Use VM_MIXEDMAP instead of VM_IO to avoid NUMA balancing xen-scsifront: Add a missing call to kfree MAINTAINERS: update XEN HYPERVISOR INTERFACE xenfs: Use proc_create_mount_point() to create /proc/xen xen-platform: use builtin_pci_driver xen-netback: fix error handling output xen: make use of xenbus_read_unsigned() in xenbus xen: make use of xenbus_read_unsigned() in xen-pciback xen: make use of xenbus_read_unsigned() in xen-fbfront ...
2016-12-13Merge branch 'stable/for-linus-4.9' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb Pull swiotlb updates from Konrad Rzeszutek Wilk: - minor fixes (rate limiting), remove certain functions - support for DMA_ATTR_SKIP_CPU_SYNC which is an optimization in the DMA API * 'stable/for-linus-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: swiotlb: Minor fix-ups for DMA_ATTR_SKIP_CPU_SYNC support swiotlb: Add support for DMA_ATTR_SKIP_CPU_SYNC swiotlb-xen: Enforce return of DMA_ERROR_CODE in mapping function swiotlb: Drop unused functions swiotlb_map_sg and swiotlb_unmap_sg swiotlb: Rate-limit printing when running out of SW-IOMMU space
2016-12-12xen/balloon: Only mark a page as managed when it is releasedRoss Lagerwall
Only mark a page as managed when it is released back to the allocator. This ensures that the managed page count does not get falsely increased when a VM is running. Correspondingly change it so that pages are marked as unmanaged after getting them from the allocator. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-12-12xenbus: fix deadlock on writes to /proc/xen/xenbusDavid Vrabel
/proc/xen/xenbus does not work correctly. A read blocked waiting for a xenstore message holds the mutex needed for atomic file position updates. This blocks any writes on the same file handle, which can deadlock if the write is needed to unblock the read. Clear FMODE_ATOMIC_POS when opening this device to always get character device like sematics. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-12-09x86: Remove empty idle.h headerThomas Gleixner
One include less is always a good thing(tm). Good riddance. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/20161209182912.2726-6-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-08xen: xenbus: set error code on failurePan Bian
Variable err is initialized with 0. As a result, the return value may be 0 even if get_zeroed_page() fails to allocate memory. This patch fixes the bug, initializing err with "-ENOMEM". Signed-off-by: Pan Bian <bianpan2016@163.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-12-08xen: set error code on failuresPan Bian
Variable rc is reset in the loop, and its value will be non-negative during the second and after repeat of the loop. If it fails to allocate memory then, it may return a non-negative integer, which indicates no error. This patch fixes the bug, assigning "-ENOMEM" to rc when kzalloc() or alloc_page() returns NULL, and removing the initialization of rc outside of the loop. Signed-off-by: Pan Bian <bianpan2016@163.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-11-30xen/events: use xen_vcpu_id mapping for EVTCHNOP_statusVitaly Kuznetsov
EVTCHNOP_status hypercall returns Xen's idea of vcpu id so we need to compare it against xen_vcpu_id mapping, not the Linux cpu id. Suggested-by: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-11-28xen/gntdev: Use VM_MIXEDMAP instead of VM_IO to avoid NUMA balancingBoris Ostrovsky
Commit 9c17d96500f7 ("xen/gntdev: Grant maps should not be subject to NUMA balancing") set VM_IO flag to prevent grant maps from being subjected to NUMA balancing. It was discovered recently that this flag causes get_user_pages() to always fail with -EFAULT. check_vma_flags __get_user_pages __get_user_pages_locked __get_user_pages_unlocked get_user_pages_fast iov_iter_get_pages dio_refill_pages do_direct_IO do_blockdev_direct_IO do_blockdev_direct_IO ext4_direct_IO_read generic_file_read_iter aio_run_iocb (which can happen if guest's vdisk has direct-io-safe option). To avoid this let's use VM_MIXEDMAP flag instead --- it prevents NUMA balancing just as VM_IO does and has no effect on check_vma_flags(). Cc: stable@vger.kernel.org Reported-by: Olaf Hering <olaf@aepfle.de> Suggested-by: Hugh Dickins <hughd@google.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Acked-by: Hugh Dickins <hughd@google.com> Tested-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-11-18x86/idle: Remove enter_idle(), exit_idle()Len Brown
Upon removal of the is_idle flag, these routines became NOPs. Signed-off-by: Len Brown <len.brown@intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: http://lkml.kernel.org/r/822f2c22cc5890f7b8ea0eeec60277eb44505b4e.1479449716.git.len.brown@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-17xenfs: Use proc_create_mount_point() to create /proc/xenSeth Forshee
Mounting proc in user namespace containers fails if the xenbus filesystem is mounted on /proc/xen because this directory fails the "permanently empty" test. proc_create_mount_point() exists specifically to create such mountpoints in proc but is currently proc-internal. Export this interface to modules, then use it in xenbus when creating /proc/xen. Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-11-17xen-platform: use builtin_pci_driverGeliang Tang
Use builtin_pci_driver() helper to simplify the code. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-11-10swiotlb: Minor fix-ups for DMA_ATTR_SKIP_CPU_SYNC supportAlexander Duyck
I am updating the paths so that instead of trying to pass "attr | DMA_ATTR_SKIP_CPU_SYNC" we instead just OR the value into attr and then pass it since attr will not be used after we make the unmap call. I realized there was one spot I had missed when I was applying the DMA attribute to the DMA mapping exception handling. This change corrects that. Finally it looks like there is a stray blank line at the end of the swiotlb_unmap_sg_attrs function that can be dropped. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
2016-11-07swiotlb: Add support for DMA_ATTR_SKIP_CPU_SYNCAlexander Duyck
As a first step to making DMA_ATTR_SKIP_CPU_SYNC apply to architectures beyond just ARM I need to make it so that the swiotlb will respect the flag. In order to do that I also need to update the swiotlb-xen since it heavily makes use of the functionality. Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
2016-11-07swiotlb-xen: Enforce return of DMA_ERROR_CODE in mapping functionAlexander Duyck
The mapping function should always return DMA_ERROR_CODE when a mapping has failed as this is what the DMA API expects when a DMA error has occurred. The current function for mapping a page in Xen was returning either DMA_ERROR_CODE or 0 depending on where it failed. On x86 DMA_ERROR_CODE is 0, but on other architectures such as ARM it is ~0. We need to make sure we return the same error value if either the mapping failed or the device is not capable of accessing the mapping. If we are returning DMA_ERROR_CODE as our error value we can drop the function for checking the error code as the default is to compare the return value against DMA_ERROR_CODE if no function is defined. Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
2016-11-07xen: make use of xenbus_read_unsigned() in xenbusJuergen Gross
Use xenbus_read_unsigned() instead of xenbus_scanf() when possible. This requires to change the type of the reads from int to unsigned, but these cases have been wrong before: negative values are not allowed for the modified cases. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: David Vrabel <david.vrabel@citrix.com>
2016-11-07xen: make use of xenbus_read_unsigned() in xen-pcibackJuergen Gross
Use xenbus_read_unsigned() instead of xenbus_scanf() when possible. This requires to change the type of the read from int to unsigned, but this case has been wrong before: negative values are not allowed for the modified case. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: David Vrabel <david.vrabel@citrix.com>
2016-11-07xen: introduce xenbus_read_unsigned()Juergen Gross
There are multiple instances of code reading an optional unsigned parameter from Xenstore via xenbus_scanf(). Instead of repeating the same code over and over add a service function doing the job. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2016-10-24Merge tag 'for-linus-4.9-rc2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from David Vrabel: - advertise control feature flags in xenstore - fix x86 build when XEN_PVHVM is disabled * tag 'for-linus-4.9-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xenbus: check return value of xenbus_scanf() xenbus: prefer list_for_each() x86: xen: move cpu_up functions out of ifdef xenbus: advertise control feature flags
2016-10-24xenbus: check return value of xenbus_scanf()Jan Beulich
Don't ignore errors here: Set backend state to unknown when unsuccessful. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-10-24xenbus: prefer list_for_each()Jan Beulich
This is more efficient than list_for_each_safe() when list modification is accompanied by breaking out of the loop. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-10-24xenbus: advertise control feature flagsJuergen Gross
The Xen docs specify several flags which a guest can set to advertise which values of the xenstore control/shutdown key it will recognize. This patch adds code to write all the relevant feature-flag keys. Based-on-patch-by: Paul Durrant <paul.durrant@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Paul Durrant <paul.durrant@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-10-06Merge tag 'for-linus-4.9-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from David Vrabel: "xen features and fixes for 4.9: - switch to new CPU hotplug mechanism - support driver_override in pciback - require vector callback for HVM guests (the alternate mechanism via the platform device has been broken for ages)" * tag 'for-linus-4.9-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/x86: Update topology map for PV VCPUs xen/x86: Initialize per_cpu(xen_vcpu, 0) a little earlier xen/pciback: support driver_override xen/pciback: avoid multiple entries in slot list xen/pciback: simplify pcistub device handling xen: Remove event channel notification through Xen PCI platform device xen/events: Convert to hotplug state machine xen/x86: Convert to hotplug state machine x86/xen: add missing \n at end of printk warning message xen/grant-table: Use kmalloc_array() in arch_gnttab_valloc() xen: Make VPMU init message look less scary xen: rename xen_pmu_init() in sys-hypervisor.c hotplug: Prevent alloc/free of irq descriptors during cpu up/down (again) xen/x86: Move irq allocation from Xen smp_op.cpu_up()
2016-09-30xen/pciback: support driver_overrideJuergen Gross
Support the driver_override scheme introduced with commit 782a985d7af2 ("PCI: Introduce new device binding path using pci_dev.driver_override") As pcistub_probe() is called for all devices (it has to check for a match based on the slot address rather than device type) it has to check for driver_override set to "pciback" itself. Up to now for assigning a pci device to pciback you need something like: echo 0000:07:10.0 > /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind echo 0000:07:10.0 > /sys/bus/pci/drivers/pciback/new_slot echo 0000:07:10.0 > /sys/bus/pci/drivers_probe while with the patch you can use the same mechanism as for similar drivers like pci-stub and vfio-pci: echo pciback > /sys/bus/pci/devices/0000\:07\:10.0/driver_override echo 0000:07:10.0 > /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind echo 0000:07:10.0 > /sys/bus/pci/drivers_probe So e.g. libvirt doesn't need special handling for pciback. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30xen/pciback: avoid multiple entries in slot listJuergen Gross
The Xen pciback driver has a list of all pci devices it is ready to seize. There is no check whether a to be added entry already exists. While this might be no problem in the common case it might confuse those which consume the list via sysfs. Modify the handling of this list by not adding an entry which already exists. As this will be needed later split out the list handling into a separate function. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30xen/pciback: simplify pcistub device handlingJuergen Gross
The Xen pciback driver maintains a list of all its seized devices. There are two functions searching the list for a specific device with basically the same semantics just returning different structures in case of a match. Split out the search function. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30xen: Remove event channel notification through Xen PCI platform deviceKarimAllah Ahmed
Ever since commit 254d1a3f02eb ("xen/pv-on-hvm kexec: shutdown watches from old kernel") using the INTx interrupt from Xen PCI platform device for event channel notification would just lockup the guest during bootup. postcore_initcall now calls xs_reset_watches which will eventually try to read a value from XenStore and will get stuck on read_reply at XenBus forever since the platform driver is not probed yet and its INTx interrupt handler is not registered yet. That means that the guest can not be notified at this moment of any pending event channels and none of the per-event handlers will ever be invoked (including the XenStore one) and the reply will never be picked up by the kernel. The exact stack where things get stuck during xenbus_init: -xenbus_init -xs_init -xs_reset_watches -xenbus_scanf -xenbus_read -xs_single -xs_single -xs_talkv Vector callbacks have always been the favourite event notification mechanism since their introduction in commit 38e20b07efd5 ("x86/xen: event channels delivery on HVM.") and the vector callback feature has always been advertised for quite some time by Xen that's why INTx was broken for several years now without impacting anyone. Luckily this also means that event channel notification through INTx is basically dead-code which can be safely removed without impacting anybody since it has been effectively disabled for more than 4 years with nobody complaining about it (at least as far as I'm aware of). This commit removes event channel notification through Xen PCI platform device. Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Juergen Gross <jgross@suse.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Julien Grall <julien.grall@citrix.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Ross Lagerwall <ross.lagerwall@citrix.com> Cc: xen-devel@lists.xenproject.org Cc: linux-kernel@vger.kernel.org Cc: linux-pci@vger.kernel.org Cc: Anthony Liguori <aliguori@amazon.com> Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30xen/events: Convert to hotplug state machineSebastian Andrzej Siewior
Install the callbacks via the state machine. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-08-24xen: rename xen_pmu_init() in sys-hypervisor.cJuergen Gross
There are two functions with name xen_pmu_init() in the kernel. Rename the one in drivers/xen/sys-hypervisor.c to avoid shadowing the one in arch/x86/xen/pmu.c To avoid the same problem in future rename some more functions. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-08-24xenbus: don't look up transaction IDs for ordinary writesJan Beulich
This should really only be done for XS_TRANSACTION_END messages, or else at least some of the xenstore-* tools don't work anymore. Fixes: 0beef634b8 ("xenbus: don't BUG() on user mode induced condition") Reported-by: Richard Schütz <rschuetz@uni-koblenz.de> Cc: <stable@vger.kernel.org> Signed-off-by: Jan Beulich <jbeulich@suse.com> Tested-by: Richard Schütz <rschuetz@uni-koblenz.de> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-08-04dma-mapping: use unsigned long for dma_attrsKrzysztof Kozlowski
The dma-mapping core and the implementations do not change the DMA attributes passed by pointer. Thus the pointer can point to const data. However the attributes do not have to be a bitfield. Instead unsigned long will do fine: 1. This is just simpler. Both in terms of reading the code and setting attributes. Instead of initializing local attributes on the stack and passing pointer to it to dma_set_attr(), just set the bits. 2. It brings safeness and checking for const correctness because the attributes are passed by value. Semantic patches for this change (at least most of them): virtual patch virtual context @r@ identifier f, attrs; @@ f(..., - struct dma_attrs *attrs + unsigned long attrs , ...) { ... } @@ identifier r.f; @@ f(..., - NULL + 0 ) and // Options: --all-includes virtual patch virtual context @r@ identifier f, attrs; type t; @@ t f(..., struct dma_attrs *attrs); @@ identifier r.f; @@ f(..., - NULL + 0 ) Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> Acked-by: Mark Salter <msalter@redhat.com> [c6x] Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> [cris] Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> [drm] Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Acked-by: Joerg Roedel <jroedel@suse.de> [iommu] Acked-by: Fabien Dessenne <fabien.dessenne@st.com> [bdisp] Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> [vb2-core] Acked-by: David Vrabel <david.vrabel@citrix.com> [xen] Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen swiotlb] Acked-by: Joerg Roedel <jroedel@suse.de> [iommu] Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon] Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390] Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> [avr32] Acked-by: Vineet Gupta <vgupta@synopsys.com> [arc] Acked-by: Robin Murphy <robin.murphy@arm.com> [arm64 and dma-iommu] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-27Merge tag 'for-linus-4.8-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from David Vrabel: "Features and fixes for 4.8-rc0: - ACPI support for guests on ARM platforms. - Generic steal time support for arm and x86. - Support cases where kernel cpu is not Xen VCPU number (e.g., if in-guest kexec is used). - Use the system workqueue instead of a custom workqueue in various places" * tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (47 commits) xen: add static initialization of steal_clock op to xen_time_ops xen/pvhvm: run xen_vcpu_setup() for the boot CPU xen/evtchn: use xen_vcpu_id mapping xen/events: fifo: use xen_vcpu_id mapping xen/events: use xen_vcpu_id mapping in events_base x86/xen: use xen_vcpu_id mapping when pointing vcpu_info to shared_info x86/xen: use xen_vcpu_id mapping for HYPERVISOR_vcpu_op xen: introduce xen_vcpu_id mapping x86/acpi: store ACPI ids from MADT for future usage x86/xen: update cpuid.h from Xen-4.7 xen/evtchn: add IOCTL_EVTCHN_RESTRICT xen-blkback: really don't leak mode property xen-blkback: constify instance of "struct attribute_group" xen-blkfront: prefer xenbus_scanf() over xenbus_gather() xen-blkback: prefer xenbus_scanf() over xenbus_gather() xen: support runqueue steal time on xen arm/xen: add support for vm_assist hypercall xen: update xen headers xen-pciback: drop superfluous variables xen-pciback: short-circuit read path used for merging write values ...
2016-07-26mm, frontswap: convert frontswap_enabled to static keyVlastimil Babka
I have noticed that frontswap.h first declares "frontswap_enabled" as extern bool variable, and then overrides it with "#define frontswap_enabled (1)" for CONFIG_FRONTSWAP=Y or (0) when disabled. The bool variable isn't actually instantiated anywhere. This all looks like an unfinished attempt to make frontswap_enabled reflect whether a backend is instantiated. But in the current state, all frontswap hooks call unconditionally into frontswap.c just to check if frontswap_ops is non-NULL. This should at least be checked inline, but we can further eliminate the overhead when CONFIG_FRONTSWAP is enabled and no backend registered, using a static key that is initially disabled, and gets enabled only upon first backend registration. Thus, checks for "frontswap_enabled" are replaced with "frontswap_enabled()" wrapping the static key check. There are two exceptions: - xen's selfballoon_process() was testing frontswap_enabled in code guarded by #ifdef CONFIG_FRONTSWAP, which was effectively always true when reachable. The patch just removes this check. Using frontswap_enabled() does not sound correct here, as this can be true even without xen's own backend being registered. - in SYSCALL_DEFINE2(swapon), change the check to IS_ENABLED(CONFIG_FRONTSWAP) as it seems the bitmap allocation cannot currently be postponed until a backend is registered. This means that frontswap will still have some memory overhead by being configured, but without a backend. After the patch, we can expect that some functions in frontswap.c are called only when frontswap_ops is non-NULL. Change the checks there to VM_BUG_ONs. While at it, convert other BUG_ONs to VM_BUG_ONs as frontswap has been stable for some time. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/1463152235-9717-1-git-send-email-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Juergen Gross <jgross@suse.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26xen: add static initialization of steal_clock op to xen_time_opsJuergen Gross
pv_time_ops might be overwritten with xen_time_ops after the steal_clock operation has been initialized already. To prevent calling a now uninitialized function pointer add the steal_clock static initialization to xen_time_ops. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-25xen/evtchn: use xen_vcpu_id mappingVitaly Kuznetsov
Use the newly introduced xen_vcpu_id mapping to get Xen's idea of vCPU id for CPU0. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-25xen/events: fifo: use xen_vcpu_id mappingVitaly Kuznetsov
EVTCHNOP_init_control has vCPU id as a parameter and Xen's idea of vCPU id should be used. Use the newly introduced xen_vcpu_id mapping to convert it from Linux's id. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>